This study used data from a prospectively maintained clinical and QoL database [7, 8]. The database is maintained through REDCap, and is managed by the Surgical Outcomes Research Centre (SOuRCe). Patients’ clinical information and QoL data is collected at baseline (for this study either preoperatively or postoperatively) and then at 6, 12, 18, 24, 30, 36, 48 and 60 months postoperative. In brief, participants for this study included patients with advanced primary or recurrent rectal cancer who underwent pelvic exenteration at the Royal Prince Alfred Hospital (RPAH) Sydney, between 2008 and 2016. Ethics approval for the QoL study was granted by the Royal Prince Alfred Research Human Research Ethics Committee (Approval Number X16-0272).
Inclusion and exclusion criteria
Patients eligible for the study was adults aged 18 years and over with non-metastatic curable locally advanced or locally recurrent cancer arising from the pelvis. Although the type of cancer is not restricted, what these cancers have in common is the need for radical multivisceral en bloc resection. Patients were also excluded if they had cognitive impairment such that they are unable to give informed consent or inadequate English to complete self-reported outcome measures.
Pelvic exenteration was defined as en bloc resection of at least three major pelvic structures which may comprise of a major pelvic organ (e.g. rectum, uterus, bladder etc.) and/or pelvic neurovascular structure, soft tissue or bony structure (e.g. iliac vessels, obturator internus, sciatic nerve roots, sacrum etc.).
Patient characteristics and quality of life measurements
Data collection at study enrolment included patient demographics, relevant clinical information as well as QoL data. For logistical reasons described above, some patients did not complete the QoL measures prior to surgery. This group of patients then completed QoL measures in the early postoperative period. Patients were specifically instructed to answer the questionnaires based on their recollection of their preoperative QoL status. The QoL questionnaire used at preoperative or postoperative was identical (i.e. same instruments were used).
The SF-36 was used to evaluate health related QoL . It is a broad measure compared with other patient-reported outcome measures, which are either disease-, treatment- or symptom-specific, and provides two summary scales (physical and mental component summary scales) plus eight domain-specific subscales (vitality; physical functioning; bodily pain; general health perceptions; physical role functioning; emotional role functioning; social role functioning; and mental health). QoL data was scored for the preoperative and postoperative groups using SF-36 Scoring Software. Higher SF-36 scores indicate better QoL.
Baseline pre- and postoperative demographics, clinical characteristics and QoL scores were summarised as mean ± standard deviation for continuous outcomes or as frequencies (percentage) for dichotomous outcomes. Differences between the pre- and postoperative group scores were assessed using Chi squared tests (dichotomous outcomes) or T tests (continuous outcomes) with P < 0.05 considered statistically significant. All analyses were performed using SPSS version 22 (SPSS, inc., Chicago, IL).